In general, a dental implant (hereinafter, briefly called ‘implant’) must functionally execute role for the actual tooth because the implant is an artificial tooth permanently substituting a missing tooth. Moreover, the implant must be manufactured to be used for a long time by properly dispersing load applied to the teeth during mastication, and must be manufactured as accurate as it is little different in form and color from the actual tooth in an aspect of beauty.
The implant is transplanted and fixed into the tissue inside the oral cavity, namely, the alveolar bone, and as time goes by after transplantation into the tissue, the implant is corroded by tissue fluid or body fluid in the body or by elution of metal ions of the metal implant due to contact and friction with the tissue. Moreover, the metal ions eluted from the metal implant damage macrophages in the body or invade the cells in the body so as to cause generation of inflammatory cells or giant cells, and hence, the implant must have excellent biocompatibility.
In an aspect of materials for such an implant, there have been various attempts to use metals and alloys, but titanium metal or titanium alloys which have high bioaffinity, mechanical intensity and bio-inactivity in respect of the tissues of the human body have been mainly used.
In the meantime, for a stable osseointegration of the implant inside the body, a method of widening the surface area getting in contact with the tissue by increasing surface roughness of the implant has been used. The SA (Sandblasting with large grit and Acid treatment) method which is a representative method for increasing the surface area of the implant blasts Al2O3 particles onto the surface of the implant in order to generate craters and micro-pits, and then, treats strong acid (H2SO4/HCl), and hence, as a result, has an effect to increase the surface area by more than 40 percent in comparison with the conventional RBM (Resorbable Blasting Media) method. Therefore, the implant produced by the SA method after blasting of the particles can reduce the average curing period by six weeks to eight weeks from twelve weeks.
However, the surface of hydrophilic titanium surface-treated by the SA method has a demerit in that it is rapidly hydrophobized by irreciprocal absorption of carbon pollution sources in the air.
Because the hydrophobized surface hinders an inflow of bone cells to the surface of the implant so as to reduce a contact ratio between the bone and the implant from the beginning of the implant procedure, it may be a potential cause of failure of the implant procedure.
Therefore, countermeasures for maintaining the hydrophilic property by preventing hydrophobization of the surface of the titanium implant manufactured by the SA method in the air have been prepared. A representative countermeasure of the countermeasures is to cut off contact with the air by putting and packing the titanium implant into a container filled with water or inert gas so as to cut off contact with the air.
The above packing method is very effective in an aspect of maintaining hydrophilic property of the surface of the titanium implant, but there is a restriction in use front the standpoint of the recent development direction of implants. That is, the recent development point of implants is to reduce the period of the implant procedure by coating the surface of the implant with chemical material, peptide or protein which can promote osseointegration. However, there is no verification on what happens when the implant which is coated with such a material is covered with water, and if it has a bad influence on the implant, it is necessary to look for another packing media which can solve the above-mentioned problem.
Therefore, with a new concept different from the packing method for creating the conventional inert environment, a development of a new implant packing which can prevent hydrophobization of the surface of the implant and maintain the hydrophilic property of the surface is needed.